Cog is a small tool I wrote years ago. It finds snippets of Python in text files, executes them, and inserts the result back into the text. It’s good for adding a little bit of computational support into an otherwise static file. Originally I wrote it to generate boilerplate C code, but now I use it for making all my presentations.

It has sat dormant for a long time. Recently someone asked me if it was maintained, and I huffily answered, “it’s maintained as much as it needs to be.” But they were right to ask: it certainly had the look of an abandoned property.

So I jumped in and did a bunch of work to it. Development moved from Bitbucket to GitHub. I merged a few pull requests. I added Travis and Appveyor CI.

The biggest functional change is that errors during execution now get reasonable tracebacks that don’t require you to reverse-engineer how cog ran your code.

I even used mutmut to add a few more tests.

The result is Cog 3.0, ready for your use! I’ll try to stay on top of it better now, I promise!